Joy Corporation manufactures a product with the following per unit standard costs: Direct Materials 10 square yards at $6 per yard Direct Labor 12 hours at $10 per hour The following information relates to actual operations: Direct materials purchased = 1000 square yards at $5 per yard Direct materials used in production = 900 square yards Direct labor cost = $10,000 Direct labor hours = 1,200 Actual output = 80 units The direct labor efficiency variance is: a. $2,000 favorable b. $2,000 unfavorable c. $2,400 favorable d. $2,400 unfavorable